Atmospheric Mass & Pressure
"Air pressure is the force exerted by the atmospheric air on the surface of the planet. It changes with altitude and temperature. The higher the elevation, the smaller is the mass of the air overlying the ground. Also, atmospheric pressure increases with the increase in temperature."
https://www.omnicalculator.com/physics/air-pressure-at-altitude
"Atmospheric pressure is the pressure exerted by the weight of the Earth's atmosphere. It varies with altitude because the weight of air present above the point of measurement changes. And since air is denser at sea level than at higher altitudes, you can understand that the air pressure decreases as the altitude increases."
https://www.calctool.org/atmospheric-thermodynamics/air-pressure-at-altitude
Water Mass & Pressure
"At sea level, the air that surrounds us presses down on our bodies at 14.7 pounds per square inch. You don't feel it because the fluids in your body are pushing outward with the same force.
Dive down into the ocean even a few feet, though, and a noticeable change occurs. You can feel an increase of pressure on your eardrums. This is due to an increase in hydrostatic pressure, the force per unit area exerted by a liquid on an object. The deeper you go under the sea, the greater the pressure of the water pushing down on you. For every 33 feet (10.06 meters) you go down, the pressure increases by one atmosphere."
https://oceanservice.noaa.gov/facts/pressure.html
Gravity & Mass
"The standard acceleration of gravity or standard acceleration of free fall, often called simply standard gravity and denoted by ɡ0 or ɡn, is the nominal gravitational acceleration of an object in a vacuum near the surface of the Earth. It is a constant defined by standard as 9.80665 m/s2 (about 32.17405 ft/s2)."
https://en.m.wikipedia.org/wiki/Standard_gravity
"At a certain altitude, known as the “zero gravity” or “microgravity” environment, the gravitational pull becomes negligible."
https://www.ncesc.com/geographic-faq/at-what-altitude-does-gravity-stop/
"Gravity impedes the flow of time, which implies that the more massive the object, the slower time passes in its vicinity."
https://www.scienceabc.com/nature/universe/time-dilation-why-does-gravity-slow-down-the-flow-of-time.html
"According to Einstein’s theory of gravity, general relativity, clocks tick faster the farther they are from Earth or another massive object (SN: 10/4/15)."
https://www.sciencenews.org/article/atomic-clock-general-relativity-time-warp-millimeter-physics
"Time slows down near a black hole due to the extremely strong gravitational field of the black hole."
https://profoundphysics.com/why-time-slows-down-near-a-black-hole/
"Anything that has mass also has gravity. Objects with more mass have more gravity"
https://spaceplace.nasa.gov/what-is-gravity/en/
"Force = [gravitational constant x masses (m1 m2)] / (radius)2"
https://www.toppr.com/guides/physics-formulas/gravity-formula/
High altitude, zero atmosphere = “zero gravity”
Sea level, one atmosphere(14.7 psi) = "one gravity"(9.80665 m/s2)
"For every 33 feet(10.06 meters) you go down, the pressure increases by one atmosphere"
2,000 feet below sea level. 2,000 ÷ 33 = 890.90909090909 psi or 60.606060606060G